1. Field of the Invention
The invention relates to an image capturing apparatus and an image processing method thereof and more particularly relates to an image capturing apparatus and an image smooth zooming method thereof.
2. Description of Related Art
At present, the zoom modes of a digital camera in the market include optical zoom and digital zoom. The optical zoom changes the focal length of a lens to zoom captured images by moving the lens. The optical zoom is a method of capturing the image data with the same number of pixels when magnifying the image, and therefore the magnified image can still maintain the original resolution. On the contrary, the digital zoom directly crops a portion of the original image, and then enlarges the portion and displays the enlarged portion on the screen. Although both zoom modes can provide magnifying effect of solid images, only optical zoom can still maintain the original optical resolution and image quality. Digital zoom produces an image of lower optical resolution since the number of pixels decreases with the enlargement of the image.
Optical zoom lens needs space to move lens elements of an optical lens and the lens size is relatively large, and therefore the configuration is not suitable for mobile phones, tablets or other thin devices. To make a thin device also have a better zoom effect, some products currently in the market may use dual lenses. A wide-angle lens having a wider field of view (FOV) and a telephoto lens having a narrower FOV are both deposited on one apparatus to simultaneously capture wider view images and narrower view images. One of the images captured by the two lenses is selected for zooming according to user's magnification adjustment, and finally a magnified image desired by the user is provided.
However, a dual lens camera has a problem of scrambled images when switching between the images described above, which results in non-smooth image zooming. In addition, to provide the dual-lens camera with an anti-handshake function, both lenses are required to be disposed with anti-handshake assemblies. As a result, not only the manufacturing cost rises, but also the shake-reducing effect is not notable.